Each of the below U.S. Patents and Patent Applications are hereby incorporated by reference herein in their entirety.
U.S. Pat. Nos. 8,762,022 and 9,156,536 disclose systems and methods for efficiently changing controlled engine speed of a marine internal combustion engine in a marine propulsion system for propelling a marine vessel. The system responds to the operator changing the operator-selected engine speed, from a first-selected engine speed to a second-selected engine speed, by predicting throttle position needed to provide the second-selected engine speed, and providing a feed forward signal moving the throttle to the predicted throttle position, without waiting for a slower responding PID controller and/or overshoot thereof, and concomitant instability or oscillation, and then uses the engine speed control system including any PID controller to maintain engine speed at the second-selected engine speed.
Unpublished U.S. patent application Ser. No. 14/570,760, filed Dec. 15, 2014, discloses a method for controlling a position of an electronic throttle valve of an internal combustion engine. The method includes determining a desired throttle valve position; determining a first feed forward signal based on a rate of change between a previous throttle valve position and the desired throttle valve position; and determining a second feed forward signal based on a comparison of the desired throttle valve position to a limp home position of the throttle valve, in which the throttle valve is biased open by a spring. A summation of the first and second feed forward signals is used to actuate the throttle valve. After the throttle valve has been actuated according to the first and second feed forward signals, the position of the throttle valve is controlled with a feedback controller to obtain the desired throttle valve position.
Unpublished U.S. patent application Ser. No. 14/573,202, filed Dec. 17, 2014, discloses a method for setting an engine speed of an internal combustion engine in a marine propulsion system to an operator-selected engine speed. The method includes predicting a position of a throttle valve of the engine that is needed to provide the operator-selected engine speed, and determining a feed forward signal that will move the throttle valve to the predicted position. After moving the throttle valve to the predicted position, the method next includes controlling the engine speed with a feedback controller so as to obtain the operator-selected engine speed. The feed forward signal is determined based on at least one of the following criteria: an operator-selected control mode of the marine propulsion system and an external operating condition of the marine propulsion system. A system for setting the engine speed to the operator-selected engine speed is also described.
Unpublished U.S. patent application Ser. No. 14/610,377, filed Jan. 30, 2015, discloses a method for setting an engine speed of an internal combustion engine in a marine propulsion device of a marine propulsion system to an engine speed setpoint. The method includes determining the engine speed setpoint based on an operator demand and predicting a position of a throttle valve that is needed to achieve the engine speed setpoint. The method also includes determining a feed forward signal that will move the throttle valve to the predicted position, and after moving the throttle valve to the predicted position, adjusting the engine speed with a feedback controller so as to obtain the engine speed setpoint. An operating state of the marine propulsion system is also determined. Depending on the operating state, the method may include determining limits on an authority of the feedback controller to adjust the engine speed and/or determining whether the operator demand should be modified prior to determining the engine speed setpoint.